The following sample data are from a normal population: 10, 8, 11, 12, 9, 10, 14, 13,6
a. What is the sample mean x̅?
b. What is the sample standard deviation s?
c. What is the 95% confidence interval for the population mean?
We have for given data,
a)
Sample mean =10.33........................using AVERAGE command in
Excel.
b)
Sample standard deviation =2.5..........................using STDEV
in Excel.
c)
Sample size = 9
Level of significance= 0.05
Degree of freedom = 8
t critical value is (by using t table)=
2.306
Confidence interval formula is
=(8.41,12.25)
Lower confidence limit= 8.41
Upper confidence limit= 12.25
The following sample data are from a normal population: 10, 8, 11, 12, 9, 10,...
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